Engine-starting apparatus



Sept. 7 1926.

- F. c. KROEGER ENGINE STARTING APPARATUS V 2 Sheets-Sheet 1 Filed April1, 1924 Sept. 7,1926. 1,598,826

F. c. KROEGER ENGINE STARTING APPARATUS Filed April 1, 1924 2Sheets-Sheet 2 Patented Sept. 7, 1926.

UNITED STATES PATENT OFFICE.

FREDERICK C. KROEGER, OF ANDERSON, INDIANA, ASSIGNOR T GENERAL IOTORBCORPORATION, A CORPORATION OF DELAW ENGINE-STARTING APPARATUS.

Application filed April 1,

This invention relates to starting apparatus for internal combustionengines, particularly, to a type of apparatus including an electricmotor operating a gear which is movable axially into engagement with agear connected with the engine such as the engine flywheel gear.

Among the objects of the invention are the connecting of the motor gearwith the engine gear and the operating the motor by manual operation,for example, by means of a starting lever, and the demeshing of themotor gear from the engine gear automatically when the engine starts reardless of whether the starting lever is stiil maintained in enginestarting position.

A further object is to prevent connection of the motor gear with theengine gear while the engine is self operative.

In order to accon'iplish these objects the invention provides meansresponsive to the rotation of the engine during cranking, said meansbeing controlled by the suction of the engine for disconnecting thestarting motor pedal from a device which engages the motor gear to shiftit axiallv into engagement with the flywheel gear. The motor gear isconnected. with the motor shaft by a spiral spline or screw thread.Consequently when the engine becomes self-operative, the motor gear willbe automatically demeshcd from the engine gear, although the startingmotor pedal may not yet be released by the operator. This suctionoperated means also prevents connecting the pedal with the motor gearshifting means while the engine isrunning.

Further objects and advantages will be apparent from the followingdescription, reference being had to the accompanying drawings, whercinapreferred form of embodiment of the present invention is clearly shown.

In the drawings:

Fig. 1 is a fragmentary side view partly in section of a starting motorand gearing including a form of the invention, the apparatus being innormal or inoperative condition.

Fig. 2 is a view similar to Fig. 1 but showing the gear shifting andmotor controlling I apparatus in position for cranking the en 1924.krill No. 708,532.

the control lever disconnected from the device for moving the motorpinion.

Referring to the drawings, 20 designates a gear housing including abracket 21 for supporting thehousing upon the frame of an engine notshown but represented in the drawlngs by an engine flywheel gear 22. Thehousmg 20 supports a motor field frame 23. By means of a bearing notshown the frame 23 supports the motor shaft 24 having one end 'ournaledat 25 in the gear housmg 20. he shaft 24 is provided with a spirallysplined or threaded portion 26 which engages an internall threaded motorgear 27 carryin a flange washer 28 proectmg beyond t e periphery of thegear. The motion transmitting device for shiftmg gear 27 endwise intoengagement with the gear 22 includes a bifurcated lever 29 pivoted upona shaft 30 carried by housmg 20, the bifurcations of lever 29 beingconnected by a yoke 31 and the ends thereof being rounded. at 32 toengage a grooved collar 33. Between collar 33 and the end 34 of thearmature core there is located a spacer 35. A- spring 36, coiled aroundthe shaft 30 has one end 37 bearing against the gear housing 20 andagainst the yoke 31. Between the groove collar 33 and the gear 27 thereis located a spring 40 held in an initial state of vcompression by meansof sprin housing members 41 and 42 which limitt e separation of members33 and 27. Housing member 41 is attached as shown in Fig. 1 to thecollar 33 and is provided with a flan e 43 connected with a flange 45 ofthe member 42 by lugs 44 integral with flange 45 and bent around flange43. Member 42 in provided with an opening 46 which is large enough toclear the motor gear 27 but is smaller in diameter than the externaldiameter of the washer 28. The manually operable means for moving themotion transmitting device includes a lever 50 pivoted upon the shaft 30and carrying an adjustable screw 51 adapted to engage the plunger 52 ofa motor operating switch enclosed within a housing 53. One terminal ofthe switch for connection with a current source is shown at 54 and theother terminal not shown is connected with the motor field circuit. Thelever 50 is operated by a rod 55'carrying a pedal 56 located inconvenient reach of the driver.

The means for connecting the lever with a gear shifting lever 29includes a pawl 60 pivoted upon a stud 61 carried by lever 50. The pawlengages a notch 62 in the lever 29 and is normally held in this positionby means of a spring 63 coiled around the stud 61 and having one end 64bearing against an ear (S5 of the pawl 60, said ear being at rightangles to the main portion of the pawl 60. The other end 66 of spring 63bears against a stud 67 on lever 50. The ear (35 of pawl 60 is providedwith a hole 68 for receiving a nut 69 which is threaded on a rod 7 0 andis provided with a hexagonal head 71. One end of rod 70 is connected byspring 72 with a bracket 7 3 attached to the motor field frame 23. Theother end of rod 70 is attached to a bell-crank lever 74 pivoted upon ascrew 7 5 attached to a bracket '76. Bracket 76 includes a shelf 7 7provided with a hole '78 through which extends a rod 79 having athreaded portion engaged by nuts 80 and 8 1. The end of th rod 79 belowthe shelf 77 is pivotally connected at 82 with the upper end of aflexible metal bellows 83 havingits lower end 84 connected by wire 85with bell-crank lever 74. The bellows 83 is connected by pipe 86 withthe intake manifold of the engine not shown.

A collar 90 is attached to the motor shaft 24 and 'a thrust washer 91 islocated between the collar 90 and a plane surface 92 formed on thehousing 20.

i The manner of operating the invention is as follows:

hen the engine is at rest the starting apparatus is normally in theposition shown in Fig. 1. To start the engine a pedal 56 is depressedcausing the lever 50 to move into the position shown in Fig. 2 to effectthe movement of the lever 29 and the closing of the motor switch bydepressing the plunger 52 to the position shown in Fig. 2. In case theteeth of the gear27 register with the tooth spaces of the gear 22 the enagement of these gears will take place before the motor switch isclosed. But in case of tooth abutment the spring 40 will he compremedbeyond its initial state of compression as the. collar 33 is moved tothe dotted line position 33 shown in Fig. 2, thus permitting the motorswitch to be closed. The motor will then turn to register the gear 27for enmeshment with the gear 22, and slight rotation of gear 27 willrelease the spring 40 which will quickly jump the gear 27 intoengagement with the gear 22. After the gear 27 has been moved endwisealong the shaft until it engages the collar 90, the gear 27 will turnwith the shaft 24 to operate the engine gear 22. This engine crankingposition of gear 27 is shown in Fig. 2.

During movement of gear 27 into mesh with ear 22, the awl 60 will strikethe nut head 1 and pro uce a pull on the bellows 83, tending to pull thepawl 60 out of the notch 62. The pawl and notch are so shaped that thepawl 60 will not be released unt1l the driving pressure of the pawlagainst the lever 29 is relieved. This pressure is relieved by theoperation of the motor which urges the gear 27 against the collar 90 dueto the end thrust produced by the spiral splines. Therefore, collar 33tends to move the lever 29 away from the end of the pawl 60. In Fig. 2the dotted line position 33 shows the extent to which the collar 33 canbe moved to the right by pedal operation, and the full line positionshows the positions to which the collar 33 can be moved by the operationof the motor. Hence it is apparent, after gear meshment, pawl pressureon lever 29 is relieved.

During engine cranking, as shown in Fig. 2, engine suction is suflicientto cause the bellows 83 to move awl 60 away from notch 62, after the awlriving pressure has been relieved in t e manner stated. \Vhen the enginebecomes self operative, this suction will be even greater; andtherefore, the gear 27 will be automatically demeshed although thestarter pedal may still be held down.

As shown in Fig. 3, the motor gear 27 cannot be connected with theengine while the engine is self operative, because the vacuum in bellows83 is then sufiicient to cause the bellows, operating through nut head71, to hold ear of pawl 60 in such position that when the lever 50 isrotated counterclockwise, the pawl 60 will be retracted from notch 62.It will be noted that the bellows is now able to retract the pawl 60,although pawl driving pressure had not been previously relieved.

The demeshing of the gear 27 is assisted by spring 36 which maintainsthe gear shifting mechanism in position shown in Fig. 3. The spacer 35limits the endwise movement of the collar 33 to the left as viewed inFig. 3.

To stop the motor the operator releases the pedal 56. A spring 56'.located between the pedal and the stationary part such as the floorboard 56" of the vehicle causes the lever 50 to return to the positionshown in Fig. 1. A slight clearance between the pawl (30 and lever 29 isprovided in the normal at rest position of the apparatus, so that thepawl 60 will then enter the notch 63.

It is apparent therefore, that the starting apparatus will not bedamaged by failure to release the pedal 56 as soon as the engine starts.Automatic demeshment of gear 27 will take place regardless of the statusof the starting pedal 56. Therefore the present invention avoids the useof an overrunning clutch connecting the motor armature wit startinggears in order to protect the armature against excessive rotation whenthe engine starts.

Since the gear 27 cannot be moved into mesh with the engine gear 22,while the engine is running, no damage to the gear teeth can occur by 0eratin the pedal 56.

While the orm o embodiment of the present invention as herein disclosed,constitutes a preferred form, it is to be under stood that other formsmight be ado ted, all comin within the scope of the c aims which folow.-

What I claimis as follows:

1. Engine starting apparatus comprising, in combination, an enginehaving a gear; a motor and gear driven thereby; a motion transmittingmember for meshing the motor gear with the engine gear; a manuallyoperable member for actuating the motion transmitting member; an engineoperated device for disconnecting said members before the engine becomesself-operative and for reventing reconnection of said members w lo theengine is running; and automatic means for demeshing the motor gear.

2. Engine starting apparatus comprising, in combination, an enginehaving a gear; a motor and gear driven thereby; a motion transmittingmember for meshing the motor gear with the engine gear; a manuallyoperable member for actuating the motion transmitting member, and forcau the motor to operate; an en ine 0 rate device for disconnecting saimem rs before theengine becomes self-operative and for preventingreconnection of said members while the engine is running; and automaticmeans for demeshing the motor gear.

3. Engine starting apparatus comprising in combination, an engine havinga gear; a motor and gear driven thereby; a motion transmitting memberfor meshing the motor gear with the engine gear; a manually operablemember for actuating the motion transmitting member; means responsive toengine suction for automatically disconnecting said members; andautomatic means for demeshe ing the motor gear when the engine starts.4. Engine starting apparatus comprising, in combination, an enginehaving a gear; a motor and gear driven thereby; a motion transmittingmember for meshing the motor gear with the engine gear; a manuallyoperable member for actuating the motion transmitting member; meansresponsive to engine suction for automatically disconnecting saidmembers and for preventing reconnection of said members while the engineis running; and automatic means for demeshing the motor gear when theengine starts.

5. Engine starting apparatus comprising,

in combination, an engine having a gear;

- motor and a motor and gear driven thereby; a motion transmittin memberfor meshing the motor gear with t e engine gear; a manually operablemember for actuating the motion transmitting member; means responsive toengine suction for automatically disconnectin said members before theengine becomes se -operative, and for preventing reconnection of saidmembers while the en 'ne is running; and automatic means for emeshingthe motor gear when the engine starts.

6. Engine starting apparatus comprising, in combination, an enginehaving a gear; a motor and gear driven thereby; a motion transmittinglever for meshing the motor gear with the engine gear; a manuallyoperable lever for means normally connecting said levers; engineoperated means for automatically disoonnectin said levers before theengine becomes sel -operative; and automatic means for demeshing themotor gear when the engine starts.

7. Engine starting apparatuscomprising, in combination, an engine havinga gear"; a motor and gear driven thereby; a motion transmittin lever formeshing the motor gear with tl e engine gear; a manually operable leverfor actuating the first lever; a pawl pivoted on the second lever andnormally engaging the first lever; engine operated means for causingsaid pawl to be disengagfd from the first lever before the engine eoomesself-operative; and automatic means for deme the engine starts.

8. Engine starting apparatus comprising, in combination, an enginehaving a gear; a gear driven thereby" a motion transm1ttmg lever formeshing the motor gear with the engine gear; a manually operable leverfor actuating the first'lever; a pawl pivoted on the second lever andnormally engaging the first lever; means controlled by engine suctionfor causin said pawl to be disengaged from the fir'stever; and automaticmeans for demeshing the motor gEar when the engine starts.

9. ngine starting apparatus comprising, in combination, an engine havinga gear; a motor and shaft driven thereby; 'a motor gear spirally splinedto said shaft; a motion transmitting member for moving the motor gearaxia ly into mesh with the engine gear; a manually operable member foractuating the motion transmitting memberand automatic means fordisconnecting said members before the engine starts, whereb to permitthe motor gear to be automatica ly demeshed from the engine gear.

In testimony whereof I hereto afiix my signature.

FREDERICK C. KROEGER.

ng the motor gear when actuating the first lever;

